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Author: Simon Singh

Singh recounts the history of cryptography, starting from the primitive ciphers used in ancient times, through the famous protocols used in World Wars I and II, and up to the current state of the art in public key cryptography, including a brief tour of quantum cryptography. His discussion starts with the famous Caesar Cipher, which simply shifts the plaintext alphabet by a fixed number of positions to obtain the ciphertext alphabet, which is easily broken by frequency analysis. He then progresses to more advanced polyalphabetic ciphers, which switch between different Caesar shifts over the course of a message, which culminated in the Vigenere cipher that was popular in World War I. Again the Vigenere cipher can be broken by a more careful frequency analysis and Singh details how one can do this with a fairly simple example. He continues to World War II, where the German Enigma machine presented itself as a new challenge for cryptanalysts. Here the work of several British mathematicians, including Alan Turing, ended up breaking the Enigma code, but the technique is quite complicated and very heuristic. Next, he discussion the famous Diffie-Hellman key exchange protocol and RSA public key cryptography, both of which are still in use today. Finally he presents some more theoretical topics, namely how quantum computers can possibly used to break RSA and how quantum cryptography offers a truly unbreakable cryptography protocol. Singh also goes on several tangents, discussing the Navajo Whisperers, archaeological decoding, and some legends involving cryptography.

He’s narrative is framed as an arms race between the code makers and the code breakers, and one of the prominent themes of the work is that necessity is the mother of invention. In other words, there is no need for innovation if the current state of the art is good enough. This happened many times on the side of the code makers, if their existing messages could not be decrypted, then there appeared to be no motivation to develop stronger protocols. Similarly, on the side of the code breakers, if their techniques worked well enough to decipher enemy messages (or if there was no threat from an enemy), there was no need to develop more advanced methods. This is why a lot of the advancement in cryptography, on both sides, takes place during times of war.

Another interesting theme is how secretive all of the advancements and cryptanalysis research was until very recently, and also how important it was that things remain secret. When the Vigenere cipher was broken, the British government successfully covered up the fact that it was broken and the Germans continued to use it throughout World War I. Only before WWII did it become apparent that the British could read messages encrypted by the Vigenere cipher, prompting the Germans to develop the Enigma machine. It is also interesting to know that both RSA and Diffie-Hellman key exchange were independently discovered by British academics, but this information was not released to the public until very recently.

Overall, “The Code Book” combines elements of science, mathematics as one would expect, with interesting historic, political and personal elements as Singh introduces all of the major players in the cryptographic arms race. Most of the cryptography itself is fairly primitive, because for much of history things were done by hand, and the resulting protocols are far from secure in the age of computers. However, this progression set the stage for the modern cryptographic protocols which are now in widespread use.

As far as a “The Code Book” is a popular-science book, I did not get too much out of the book, probably because I already know a decent amount about cryptography. In many cases it was obvious to me where the primitive protocols broke down and how one could break them. However, when viewed as a historian, I found it interesting to see how and why cryptography has developed to where it is today.

Author: Ray Bradbury

In Fahrenheit 451, Bradbury describes a dystopian supposedly-futuristic society in which reading is not allowed. This policy is enforced by book burnings orchestrated by government-employed firemen. The novel follows Guy Montag, a fireman who starts questioning the censorship policy after meeting a young girl with a unique curiosity, and after he watches a woman voluntarily burn herself alive with her books. He collects some books and starts reading them, but is soon found out and forced to flee the city. He escapes and runs into some other fugitives living in the forest. These people have memorized whole books and serve as the protectors of literature, waiting for a era devoid of censorship. At the end of the story, war breaks out and the city is bombed, leaving the exiled people to rebuild the city (presumably also the country) and start the new era.

Bradbury prediction about the future is not entirely inaccurate. His main qualm is that technology has changed the pace of life and how people think to a point that creative, inquisitive thinking does not happen anymore. Specifically his criticism is against television, but I would argue that many other technological advancements are contributing to this transformation. Now days it is increasingly common that people are unwilling to devote more than a couple of minutes to any single task and consequently people are not informed to the point where they can make educated decisions and ask provoking questions. The increasing popularity of twitter as a media source is evidence for this phenomenon. I don’t mean this as a criticism of twitter, it is actually a criticism of the population, who soaks up an application that is just providing what they want. This is along the same lines as Bradbury’s criticism; the media is giving people what they want, the problem is that people prefer television, news clips to potentially more intellectual tasks like reading literature.

Another related theme is that people are wrapped up in their own fantasy worlds, often oblivious about reality. This results in less stimulating conversations with people as well as a lack of appreciation for complex things like natural beauty. My guess is that this also contributes to people’s preference toward television and mass media. In Fahrenheit 451 this theme is portrayed by Mildred Montag, Guy’s wife, who is constantly listening to the radio or watching tv, ignoring Guy’s existence and oblivious to her surroundings.

This theme again is becoming more and more pertinent to our society, where people are always listening to music, on their smartphones, or otherwise unaware of their environment and the people around them. This is one of my main criticisms with smart phones and I really believe that it is ruining society, so I was glad that Bradbury wrote about it in Fahrenheit 451. On my bus ride to school, everyone is listening to music or playing games on their phones, making it that much harder to strike up potentially stimulating conversations. At meals people are constantly distracted by their smart phones that conversation becomes much more superficial and uninteresting. Needless to say, I find it incredibly annoying.

Technology has a lot to offer in terms of efficiency, but there are negative side effects, like hindering social interaction and decreased attention span, that are often neglected but are also hard to quantify. How do we combat these negative side effects, so that we can enjoy the positives? For one, we can consciously avoid using technology in places where we could be interacting with other people. My friends have a “no phones at the dinner table rule” which I think is a great example of this. I also generally try to avoid using my cell phone when I am with other people, but it is important that everyone buys into this. As far as decreasing attention span, one solution is to promote reading literature. I think this is the approach Bradbury is aiming for.

So to summarize, Fahrenheit 451 is very applicable to modern society. It is interesting, well written, and its implications to our world are certainly thought provoking and hopefully inspirational.

Author: Christopher McDougall

In “Born to Run,” sports journalist McDougall helps organize an epic 50-mile race between some of the best long-distance runners in the world. These athletes include several champion ultra-marathoners from the U.S. as well as several Tarahumara, a native american people living in the Copper Canyons of Mexico. Organizing the race is challenging, as the Tarahumara typically keep to themselves and don’t tend to leave their homelands, meaning that the American athletes would have to venture into the dangerous, harsh terrain of the canyons. Yet, the actual race is, while exciting, not a critical point of the book. Rather, McDougall conducts interviews with many of the American athletes, providing insight into motivational, evolutionary and physiological aspects of running that can change the way recreational runners think about running. Additionally, the histories of many of these athletes, particularly the history of the Tarahumara competing with Americans, is fascinating in its own right.

Two interesting asides are biological in nature. The first takes an evolutionary biology perspective at answering the question “why is it reasonable to think that humans can run ultramarathon distances (30+ miles)?” The answer lies in the fact that humans used to be persistance runners, who chased their prey at a leisurely pace for miles until their prey literally collapsed with exhaustion. A morphological study of humans reveals that we are uniquely adapted to this form of hunting, in that we stand upright so that our lungs do not collapse as we run, our hamstrings, essential for running, are very strong, and we can breathe effectively while running, rather than needing to stop and pant (like many quadrupeds). It turns out that this form of hunting was much better suited to the changing climate (post ice-age) when humans ousted Neanderthals (which may be a different species) as the dominant species. Persistance hunting is still practiced in some parts of Africa, and it is not uncommon for hunters to run tens of miles. In light of this, ultramarathons do not seem all that crazy.

Another interesting aside in “Born to Run,” and probably the sticking point with so many runners, is the argument for barefoot running. McDougall cites evidence showing that many running shoes offer too much padding, changing the way that we run and actually increasing the likelihood of overuse- and impact-related injuries. On the other hand, running barefoot allows us to run naturally, in accordance with our physiological design, and not only reduces injuries but has the added benefit of being more efficient so that we actually run faster. This sort of thinking has become popular recently and has sparked a new barefoot running movement, backed by top physiology researchers.

The athletes in “Born to Run” are also quirky and their lives and past races are fascinating. It is really interesting to read about how these people started running and what drives them to keep pushing their physical limits. Apart from the biology, “Born to Run” is inspirational in that reading about these people motivates one to get running and see how far they can push their own limits. I certainly was inspired.

Author: Jack London

The first e-book I have read, “The Call of the Wild” is one of those teenage-classics that everyone reads when they are in high school. I never read it so when I found that it was free in the iTunes book store I figured I might as well. It is a good read, with interesting plot and character development, and London is a great writer, but ultimately I did not get much out of it.

The novel follows Buck, a domestic dog who gets stolen and shipped to the Yukon to be a sled dog, and his transformation from domestic to wild animal. Buck gets set up as an omega dog in a team and quickly works his way to be the head dog, become more and more aggressive and authoritative as he gains experience in the Yukon. Towards the end of the novel he becomes more and more wolf-like, ultimately actually joining a wolf pack and completing his transformation from domestic to wild. Throughout his transformation the reader learns about the tough life in the Yukon, the strenuous role of being a sled dog and also meets some interesting human and dog characters.

But apart from poetic writing, interesting plot and character development, I don’t feel like “Call of the Wild” has much to offer. The book is certainly well written; London paints vivid images of the Yukon scenery and the stories events. Moreover, It is certainly interesting to follow Buck’s transformation and one could maybe draw insight from some of his interactions with other sled dogs (i.e. how he fights only when he has too, is great at manipulating them and earning their respect) as well as some of the seemingly unnecessarily aggressive behavior of the Yukon humans, but I personally didn’t gain much from the novel. Thus, while I was not disappointed with the novel, it really is a story and not much more.

Author: Yann Martel

Disclaimer: This review will ruin the book for you if you have not read it. Please read the book (it is fairly short) and then come back here. The book is amazing so I highly recommend it anyway.

“Life of Pi” is superficially a story about a boy lost at sea and his struggle to survive. Pi Patel and his family decide to move from India to Canada, and their ship crashes in the middle of the Pacific. Pi ends up on a life boat with a tiger, a zebra, a hyena, and an orangutan, and recounts his story of how him and the tiger (Richard Parker), miraculously survive. While this story is not lacking in violence (as is natural living with a tiger), and its fair share of sadness, it is ultimately a beautiful story about friendship (between Pi and Richard Parker), cooperation, and the serenity (almost to a spiritual level) of nature.

Pi’s story is truly incredible, so when he first recounts it to two Japanese officials, they somewhat naturally do not believe him. There is no evidence that almost any part of the story is true, as Richard Parker fled as soon as they landed, and the ship had no other survivors. The Japanese officials are looking for someone to hold responsible for the crash, and Pi’s story offers no helpful evidence for them. Pi at first firmly stands his ground, maintaining that his recounting is truthful, until he realizes that the officials cannot accept anything as true unless it fits into their limited understanding of the world. Pi tells another version of the story to appease the officials; this one is horribly gruesome, involving murder and cannibalism, and showcasing the worst aspects of human nature. Yet, this story is accepted by the Japanese as truth, despite still not providing any insight into the cause of the ships sinking. The reader is left asking which account is the truth.

But in some sense, why does it matter which was factually correct? Regardless of whichever version of Pi’s adventure is correct, there are no consequences to the future of really anyone, so who cares what the truth was? Given this premise, why not believe the first, beautiful, story, which leaves you hopeful and inspired, over the second, which leaves you feeling jaded and disillusioned? I think this at least one of the takeaways of the novel. The reader fully believes the first recount, up until Pi tells the second. Immediately the reader starts doubting himself. I asked myself two related but pretty different questions when I realized this: “Why do people believe certain things but not others?” and “Why do we incessantly search for the truth, or why can’t we (read: I) believe things without proof?”

We have some intuition for what make sense and what can occur in nature, but can’t it be wrong? For example, we rely very heavily on vision and group-think to confirm truth, but then it becomes much harder to believe things that we haven’t or can not see. In fact this is a large part of why the officials do not believe Pi’s first story; the carnivorous island Pi visits has never been seen nor reported by anyone else, so they cannot imagine that it is plausible.

So what happens when our intuitions are wrong? When we find something that we cannot believe, we search endlessly for either an explanation or an alternative. As a statistics/mathematics research, I’ve notice that this happens more often than I would have thought. An exploratory stage of our work is often to conduct simulated experiments, to get a better feeling for the problem. We usually go into this stage with some intuition about the results, but in some cases the experiments do not match our intuitions. We are left searching for an explanation as to why the experiments turned out the way they did, and worse, this often results in us looking for excuses rather than changing our initial intuition (e.g. data wasn’t generated correctly, the implementation was buggy, etc.). Only when we later develop proofs do we accept changes in our intuition, because they have been mathematically verified.

A Bayesian way of looking at this is that our intuition serves as a prior for what we believe. Without any data, we tend to believe that our intuition is correct, but as we collect more and more evidence, we may become more and more confident in our intuition, but the evidence may also shift the belief away from the intuition. Different kinds of evidence have different influences, so in my previous example, simulation experiments can not unhinge my intuition but they can confirm it. Mathematical proof can do both. I think a potential problem is that we place too much weight on our prior, so that we are looking for reasons to reject other contradictory evidence. This is what seemed to happen in “Life of Pi”, as the officials rejected Pi’s first story in favor of the latter, and also what happens when I conduct statistical simulations.

The other question is much more spiritual, “why can’t we believe things without proof?” I am fundamentally a scientist, so I do not accept something as true unless I have seen a certificate (usually in the form of a proof) of its validity. And once some doubt has been introduced into my mind, I have to get to the bottom of it and uncover the truth. For example, I accepted Pi’s first story as true up until I read his second story. I started questioning his first account, and I no longer believe it. I need another, more convincing certificate to believe in that story again. Of course I doubt I will ever get a more convincing certificate, so I will always be agnostic about Pi’s story. A consequence of this is that I cannot assertively stand for something that I am agnostic about, and I remain agnostic about things until I have convincing evidence. I don’t know how people can accept something as true without evidence, maybe it is just a different interpretation of “convincing”, but there are times when I want to be able to do that.

So for example, if someone were to ask me which of Pi’s stories is true, I would say that I think the first story is true but I am not sure. This is a really wishy-washy answer and it would be much nicer to truly believe the first story is true. It seems that some people have the ability to do this, but I certainly do not. I wonder how people develop that ability.